Hypodermic syringes



IFeb. 2l, 1956 R. l.. HUBER 2,735,429

HYPODERMIC SYRINGES Filed April 2e, 1954 JNVENToR. Ralph L. Huber BydeCeOSed Jennie L. Huber admnisrotrix o* fn/mmf .4free/v51 United StatesPatent 'O 2,735,429 HYPonnRn/nc SYRINGES VRalph L. Huber, deceased, lateof Seattle, Wash., by Jennie L. Huber, administratrix, Seattle, Wash.

Application April 26, 1954, Serial No. 425,444 1 claim. (ci. Ynaam) Thisinvention relates to hypodermic syringes, and it has reference moreparticularly 'to syringes --of those kinds commonly referred to asone-'shot disposable syringes, that are designed to be used once andlthen thrown away. More specifically, the particular novelty of thisinvention resides in a new, improved and inexpensive means which makespossible the function of aspiration prior to injection of medicamentfrom the syringe into the patient.

It is the principal object of this invention to provide a hypodermicsyringe having a barrel or cylinder with a hypodermic needle sealedtherein, yand so equipped with stopples that it serves as a containerfor the medicament, and eliminates conventional glass ampules commonlyused as medicament containers in conjunction with reusable syringes, andmeans 'is provided for the vnecessary and desirable function V'ofaspirating prior to injection of the medicament.

More specically stated, the objects and advantages of the presentinvention residein the provision of a syringe comprising a cylindricalbarrel and equipped at one end with a Iclosing wall through which avdoublepointed, hypodermic needle is sealed, and fitted with a novel andimproved form of partitioning stopple which protectively overlies theinner end of the needle, and a piston stopple that is tted in the otherend of the barrel and is movable to etteet the function of aspirationand the piercing of the partitioning stopple bythe inner end of theneedle and the ultimate forcible ejection ot the medicament, containedin the barrel between the stopples, through the needle. l

It is a further object of this invention to provide a hypodermic syringeof the character above ystated wherein the novel and improved form ofpartitioning stopple is adapted or constructed so as to be effected byslight variations in pressure resulting from the manipulation vof thepiston stopple so as to produce an area of decreased pressuresurrounding the inner, pointed end of the needle. The construction andarrangement of parts further providing means whereby the end wall of thepartitioning stopple will be pierced by the needle point to permitejection of the medicament incident to the inward movement of the pistonstopple.

It is also an object of this invention to provide a new, improved andinexpensive form of partitioning stopple which will protectively overliethe inner, pointed end of the needle and wherein the end wall of thepartitioning stopple is of transparent, relatively thin, rubber orelastic type material which will respond to slight variations otpressure change.

In accomplishing the above mentioned and various other objects of thisinvention, he has provided the improved details of construction, thepreferred forms of which are illustrated in the accompanying drawings,wherein:

Fig. l is a longitudinal, cross-section view of a oneshot disposablesyringe embodying the improvements of the present invention.

Fig. 2 is an enlarged cross-sectional view of a portion of the forwardend portion of the ysyringe illustrating/the end wall of thepartitioning stopple in normal position.

Fig. 3 is an enlarged cross-sectional view similar to Fig. 2illustrating a partitioning stopple of alternative form.

Fig. 4 is a longitudinal sectional view of a one-'shot disposablesyringe embodying the alternative form 4of partitioning stopple of Fig.3 with the stopple in normal position. l

Fig. 5 is an enlarged lcross sectional View illustrating thepartitioning stopple of Fig. 3 with the end wall in outwardly cuppedposition resulting from reduction of pressure in medicament chamberincident to retraction of the piston stopple.

Fig. 6 illustrates the stopple of Fig. 3 with the 'needle piercing theend wall of the stopple to permit injection of medicament incident tothe inward movement ofthe piston stopple. l

Fig. 7 illustrates a syringe assembled 'for aspiration and injection.

Referring more in detail 'to the drawings: 4

In its present preferred form of construction, the syringe of thisinvention comprises a cylindrical barrel 10, preferably of transparentplastic, lor the like, Open at one end and closed at the vother end byan integral end wall il through which a conventional, double-pointed,hypodermic needle 12 is sealed to extend inthe a'xial center line of thebarrel; the needle being beveled to sharpened points at both its innerend 13 and its outer end 14. I t will be noted with reference to Fig. lthat the inner end of the needle extends a substantial distance into theinterior of the syringe barrel. As herein shown, the needle is formedwith an arcuate bend as at 12', which is sealed in the end wall 11 toprevent any possible slippage or movement of the needle in the Vendwall.

Applied Within the barrel, adjacent its end wall, is the barrelpartitioning stopple 20 which -is of transparent, rubber or elastic-likematerial and vwhich is of sueh diameter as to t in the barrel inrelatively tight frictional relationship. The partitioning stopple'comprises the cylindrical body 21; a relatively thin diaphr'a'gtnaticyend wall 22 which in diameter is greater than the interior /diaineterof the cylindrical body portion of the stopple and thus providing afullness of material that effects a 'reverse cupping of the wall. it isan 'important and necessary feature ofthe invention that the `end wall22 ofthe partitioning stopple 20 must be 'offsuch thickness vor weightof material that relatively sli'gh't increases or decreases in pressureapplied thereto will cause the end Wall to change its positionklso astoineiease 'the areas "surrounding the inner end of nthe -needle :andVthereby canse ha partial vacuum or an area of reduced air pressuresurrounding the end of the needle incident to the outward cupping of theend wall as illustrated in Fig. 5.

The liquid medicament M is contained in the barrel 10, in a medicamentchamber 10a between the partitioning stopple 20 and the piston stopple25, fitted in the outer end portion of the barrel, as is seen in Figs.l, 4, 5 and 6. This latter stopple 25 is of rubber, or the like and itis formed with a central, threaded socket 26 open to its outer end.

As is illustrated in Fig. 1, the outer end portion of the needle isnormally encased in a hollow guard or sheath 30, the inner end portionof which is removably fitted over a central boss or projection 11 on theend wall 11 of the barrel. About this end of the sheath is an annularlyprojecting ange 31 and at the opposite end of the sheath is a short,threaded stem .32. When the sheath has been removed from the needle, thestem 32 can be threaded into the socket 26 of the stopple 25 to attachthe part 30 to the stopple as an operating stem. The ange 31 serves as alinger grip in the manipulation of the operating stem. The open end ofthe barrel 10, likewise, is formed with an annular flange 10i and servesas a finger hold.

In Figs. 4, and 6, there is illustrated a partitioning stopple 20a ofslightly modied construction wherein the sealed area immediatelysurrounding the inner end 13 of the needle 12 is substantially reducedand wherein the stopple is at all times disposed in engagement with theend wall 11 of the barrel. The stopple of this construction will permitsubstantially freer diaphragmatic action of the end wall 22a of thestopple incident to reduced pressures in the medicament chamber a. Also,there will be substantially less compression of air in the sealed areaincident to the injection of the medicament.

With the various parts constructed as shown in Fig. l and with thebarrel properly charged with the liquid medicament, and all free airremoved from the medicament chamber, the normal use of the syringe wouldbe as follows:

First, the needle sheath, or guard 30, is removed from about the outerend of the needle and its attaching stem 32 is threaded into the socket26 of the piston stopple 25. The parts then assume the relationship asshown in Fig. 7. The needle is then inserted into the proper site orlocation in the muscle of the patient and a slight inward movement isapplied to the piston stopple 25 to cause it to move to a position wherethe end wall 22 of the partitioning stopple barely touches the inner end13 of the needle. Aspiration is then eiected by outward retraction ofthe stopple by means of the attached member 30. If a drop of bloodappears at the inner end of the needle, which blood will be visiblethrough the transparent end wall 22, this is an indication that theneedle is in a blood vein and that injection of medicament at this pointwould be dangerous and injurious to the patient. It is, therefore,required that the needle be slightly withdrawn and its directionslightly changed and again inserted to a proper depth where aspirationcan be repeated. This partial withdrawal spares the patient unnecessarypain resulting from repeated penetration of the sensory nerve in theregion of the skin surface.

When the needle is properly set, the medication is injected by applyinginward or injection pressure to the piston actuating stem 30. When thepressure is applied, the piston stopple moves inwardly causing thestopple 20 to move inwardly and the end wall 22 is pierced by the inner,pointed end 13 of the needle. The continued pressure on the pistonstopple discharges the liquid medicament through the needle into thepatient. When injection has been completed the needle is withdrawn fromthe patient and the syringe in its entirety may be discarded.

The reduced pressure in the area about the inner end of the needle andthe resulting aspiration is affected by the withdrawal of the pistonstopple thereby causing a reduced pressure or partial vacuum in themedicament chamber. This reduced pressure or vacuum will cause thediaphragmatic end wall of the stopple to be cupped outwardly as shown inFig. 5 and thereby a reduced pressure area or vacuum is caused in thesealed area or chamber surrounding the inner end of the needle.

The structure illustrated in Figs. 4, 5 and 6 is used in substantiallythe same manner as the structure of Figs. 1 and 2, except that thepartitioning stopple is disposed against the end wall 11 and thereforeit is only necessary to retract or move outwardly the piston stopple tocause the reduced pressure in the medicament chamber and the resultingreduced pressure in the area surrounding the inner end of the needle.The stopple is not moved and a tighter seal is possible between thestopple and barrel wall.

Instead of the needle herein shown, one may, if desired, alternativelyemploy a detachable, bi-pointed needle with screw on hub for itssecurement to the barrel. In such instances, the needle could, ifdesired, be reusable. Preferably the barrel is treated with siliconbefore loading with the medicament so as to protect the medicament.

The syringe structure as herein described is practical, easy to use andby reason of the elimination of the requirement for a glass ampule forcontaining the medicament, it is substantially less complicated inconstruction and is substantially more economical.

This application is a continuation-impart of allowed application, SerialNo. 307,066, led August 29, 1952 and now abandoned.

Having thus described the invention, what is claimed as new therein anddesired to secure by Letters Patent is:

A hypodermic syringe of the character described comprising a barrelformed with a closing wall at one end and a hypodermic needle sealedthrough said wall with the inner end of the needle extending into thebarrel, a partitioning stopple disposed in the balTel adjacent the saidclosing wall and a piston stopple normally disposed in the opposite endof the barrel; said partitioning stopple comprising side walls and adiaphragmatic end wall, said end wall being of relatively thin, elastic,transparent material and of substantially greater diameter than theinside diameter of the syringe barrel whereby suicient fullness isprovided to effect cupping of the end wall when the stopple is containedwithin the barrel.

References Cited in the tile of this patent UNITED STATES PATENTS1,455,047 Goold May l5, 1923 1,738,146 Kulik Dec. 3, 1929 1,860,898Meyer May 3l, 1932

